A better way to reinforce the roll cage if the roll bar sits on top of the
shoulder bar as in a rear engine lakester configuration, is to use a 4.0" long
piece of tubing as the gusset. And yes, this is an exceptable alternative to the
plates. Tubing is also a better way the reinforce a door car cage but in some
applications, it is not possible to weld the tubes all the way around. In that
case, plates should be used.
If you decide to use the plates, at least weld them exactly as the drawing in
the rule book shows, skip welded as welding them solid weakens the tube and
promotes a tearing effect in a crash.
joe
Jim Webb wrote:
> Joe,
>
> What do you mean "Forget the gusset plates..."? Even though I will not argue
> with your logic about the cage being able to
> gracefully absorb the energy of the crash, I DO wonder about passing tech.
> Would a cage without the requisite 2" x 2" gussets pass tech - Dan, J.D.?
>
> Thanks,
> Jim Webb
> jimwebb@nutsracing.com
> Chock Full o' Nuts
> #527 A/PP 193.402 2002
> B/PP 190.967 2002
> A/PP 172.695 2001
>
> -----Original Message-----
> From: owner-land-speed@autox.team.net
> [mailto:owner-land-speed@autox.team.net]On Behalf Of Joe Timney
> Sent: Sunday, October 05, 2003 8:04 AM
> To: Phillip Landry; Land-speed List
> Subject: Re: Roll Cage, again
>
> I know that many of you will disagree with this, but there is nothing wrong
> with
> the NHRA cage. The main bars should be the required tubing size but the
> support
> tubes need to be smaller. The purpose of a cage is the protect the driver by
> adsorbing the crash. If you was to build a all big tube cage, it will have
> the
> tendency to just break. Several years ago, Penske South started to building
> cars
> to absorb the impact, welding cages using Tig for strenght.
>
> And forget the gusset plates, use smaller ( 1 inch by .125 wall ) diameter
> tubing instead. It will pass tech, look at Rich Manchen's car as an example.
> Plates are prone to tear the tubing at impact.
>
> joe
|